Androgenic steroids induce pathologic scarring in a preclinical porcine model via dysfunctional extracellular matrix deposition.

Hypertrophic scarring is a major source of morbidity. Sex hormones are not classically considered modulators of scarring. However, based on increased frequency of hypertrophic scarring in patients on testosterone, we hypothesized that androgenic steroids induce abnormal scarring and developed a preclinical porcine model to explore these effects. Mini-swine underwent castration, received no testosterone (noT) or biweekly testosterone therapy (+T), and underwent excisional wounding. To create a delayed wound healing model, a subset of wounds were re-excised at 2 weeks. Scars from postoperative day 42 (POD42) and delayed wounds (POD28) were harvested 6 weeks after initial wounding for analysis via histology, bulk RNA-seq, and mechanical testing. Histologic analysis of scars from +T animals showed increased mean fibrosis area (16 mm2noT, 28 mm2+T; p = .007) and thickness (0.246 mm2noT, 0.406 mm2+T; p < .001) compared to noT. XX+T and XY+T scars had greater tensile burst strength (p = .024 and p = .013, respectively) compared to noT swine. Color deconvolution analysis revealed greater deposition of type I and type III collagen as well as increased collagen type I:III ratio in +T scars. Dermatopathologist histology scoring showed that +T exposure was associated with worse overall scarring (p < .05). Gene ontology analysis found that testosterone exposure was associated with upregulation of cellular metabolism and immune response gene sets, while testosterone upregulated pathways related to keratinization and laminin formation on pathway analysis. In conclusion, we developed a preclinical porcine model to study the effects of the sex hormone testosterone on scarring. Testosterone induces increased scar tissue deposition and appears to increase physical strength of scars via supraphysiologic deposition of collagen and other ECM factors. The increased burst strength seen in both XX and XY animals suggests that hormone administration has a strong influence on scar mechanical properties independent of chromosomal sex. Anti-androgen topical therapies may be a promising future area of research.

TMPRSS2 is a functional receptor for human coronavirus HKU1.

Four endemic seasonal human coronaviruses causing common colds circulate worldwide: HKU1, 229E, NL63 and OC43 (ref. 1). After binding to cellular receptors, coronavirus spike proteins are primed for fusion by transmembrane serine protease 2 (TMPRSS2) or endosomal cathepsins2-9. NL63 uses angiotensin-converting enzyme 2 as a receptor10, whereas 229E uses human aminopeptidase-N11. HKU1 and OC43 spikes bind cells through 9-O-acetylated sialic acid, but their protein receptors remain unknown12. Here we show that TMPRSS2 is a functional receptor for HKU1. TMPRSS2 triggers HKU1 spike-mediated cell-cell fusion and pseudovirus infection. Catalytically inactive TMPRSS2 mutants do not cleave HKU1 spike but allow pseudovirus infection. Furthermore, TMPRSS2 binds with high affinity to the HKU1 receptor binding domain (Kd 334 and 137 nM for HKU1A and HKU1B genotypes) but not to SARS-CoV-2. Conserved amino acids in the HKU1 receptor binding domain are essential for binding to TMPRSS2 and pseudovirus infection. Newly designed anti-TMPRSS2 nanobodies potently inhibit HKU1 spike attachment to TMPRSS2, fusion and pseudovirus infection. The nanobodies also reduce infection of primary human bronchial cells by an authentic HKU1 virus. Our findings illustrate the various evolution strategies of coronaviruses, which use TMPRSS2 to either directly bind to target cells or prime their spike for membrane fusion and entry.

Pain Relief with Combination Acetaminophen/Codeine or Ibuprofen following Third-Molar Extraction: A Systematic Review and Meta-Analysis.

OBJECTIVE: The purpose of our study was to perform a systematic review and meta-analysis of randomized, blinded, placebo-controlled studies that, following third-molar extraction, utilized either a combination of acetaminophen (600 mg) with codeine (60 mg) or ibuprofen (400 mg) for pain management. DESIGN: We searched PubMed, and the trial registry ClinicalTrials.gov databases with the keywords "molar or molars," "tooth or teeth," "extraction," and "pain." Selected studies were: (1) randomized, blinded, placebo controlled, (2) utilized either a single-dose combination acetaminophen (600 mg) with codeine (60 mg) (A/C) or ibuprofen, and (3) recorded standardized pain relief (PR) at 6 hours, or summed total pain relief over 6 hours (TOTPAR6). Of the 2,949 articles that were identified, 79 were retrieved for full-text analysis, and 20 of these studies met our inclusion criteria. RESULTS: For A/C, the weighted, standardized mean difference (SMD) for TOTPAR6 was 0.796 (95% confidence interval [CI], 0.597-0.995), P < .001, and for PR at 6 hours, the SMD was 0.0186 (0.007 to 0.378; P = .059), whereas for ibuprofen the SMD for TOTPAR6 was 3.009 (1.283 to 4.735; P = .001), and for PR at 6 hours, the SMD was 0.854 (95% CI, 0.712-0.996; P < .001). A SMD of 0.8 or larger is indicative of a large effect. CONCLUSIONS: Our data indicate that single dose of ibuprofen (400 mg) is an effective pain reducer for post third molar extraction pain.